1. Field of the Invention
The invention pertains to multiple station endforming machines wherein work stations are indexed about an axis of rotation during operational cycles.
2. Description of the Related Art
Endforming machines are used to axially upset elongated workpieces, usually tubes, to form the end of a tube or produce an annular enlargement or diametric reduction, and may also do rolling, assembly and other secondary operations. The endforming tool engages the end of the workpiece while the workpiece is firmly held against axial displacement. Engagement of the tool with the workpiece causes the workpiece material to deform, and the workpiece holder may include configurations to receive and shape the deformed metal during displacement of the workpiece metal by the tool.
Conventional endforming machines consist of a single work station wherein the work station includes a work holder, usually in the form of jaws, for firmly gripping and positioning the workpiece prior to workpiece deformation. After the workpiece has been firmly clamped, the endforming tool is moved into engagement with the workpiece to deform the workpiece as desired. The workpiece is then removed from the work holder. Such single work station machines, while adequately shaping the workpiece by the endforming operation, are relatively low production in that each work station must be singly loaded and unloaded, and with the plurality of machine cycling, only a single part has been shaped.
Further, if secondary operations must occur on the workpiece, it must be reclamped for each operation which reduces the workpiece diameter and hardens and stresses the workpiece.
Previous attempts to increase the production of endforming machines have not been satisfactory for a number of reasons, and until the advent of the instant invention, high production endforming apparatus has not been available.